For longitudinal field studies involving substance abusers, successfully tracking, locating, and following up with a representative sample of subjects is a challenge. One meta-analysis of 85 longitudinal studies of substance abuse clients found that nearly one-third of subjects were lost to attrition within 36 months (Hansen, Tobler, &Graham, 1990). This poses a significant threat to the validity of findings in the substance abuse (and related) fields, as follow-up rates below 80% have been shown to produce dramatically biased estimates of drug use and crime (Nemes et al., 2002). The purpose of this Phase I Small Business Technology Transfer (STTR) proposal is to develop a national network that supports a rechargeable incentive card (RIC) system designed to enhance follow-up rates. Specifically, the RIC System will involve a debit card linked to an account in which researchers can immediately transfer funds following a follow-up contact (whether this involves telephone or in-person interviews, mail-in surveys, or provision of biological samples). The card will also contain a toll-free number that subjects can use to call (as often as once a month) to notify the researchers of changes in their locator/contact information. This, too, will result in an automatic transfer of funds to the subjects'RIC System account. Developing this technology will require collaboration between the Calance Corporation and the UCLA Integrated Substance Abuse Programs (ISAP). Together, we propose to conduct a feasibility study of the RIC System, a survey comprised of a national sample of NIH-funded substance abuse researchers, and a pilot version of the accounting/tracking software and on-site card-generating machines. The proposed project will have strong commercial potential, as it will address the common problem of low follow-up rates in field studies, and there is evidence that this approach could yield rates 30 percentage points higher than those currently typical in studies of itinerant populations (Des Jarlais et al., 2005). PUBLIC HEALTH RELEVANCE: With a current annual budget of over $1 billion, NIDA supports approximately 85% of the drug abuse research conducted worldwide. It is critical that these studies of long-term drug use patterns and treatment outcome achieve follow-up rates of at least 80%. Estimates of trends or outcomes based on studies with lower follow-up rates can be invalid and misleading. Therefore, this project directly affects public health by creating a product that improves the validity and generalizability of longitudinal substance abuse research, leading to a better understanding of the nature of drug use and how best to treat it.